Heat loss from the Earth triggers ice sheet slide towards the sea

January 22, 2018, Aarhus University
Several glaciers flow into the area of Young Sound where researchers have shown that heat from the Earth's interior warms up the bottom water of the fjord. Credit: Mikael Sejr

Greenland's ice sheet is becoming smaller and smaller. The melting takes place with increased strength and at a speed that no models have previously predicted.

Today, in the esteemed journal Scientific Reports, researchers from the Arctic Research Centre, Aarhus University, and the Greenland Institute of Natural Resources present results that, for the first time, show that the deep bottom water of the north-eastern Greenland fjords is being warmed up by gradually lost from the Earth's interior. And the researchers point out that this heat loss triggers the sliding of from the ice sheet towards the sea.

Icelandic conditions

"North-East Greenland has several where the water becomes up to 60 degrees warm and, like Iceland, the area has abundant underground geothermal activity," explains Professor Soren Rysgaard, who headed the investigations.

For more than ten years, the researchers have measured the temperature and salinity in the fjord Young Sound, located at Daneborg, north of Scoresbysund, which has many hot springs, and south of the glacier Nioghalvfjerdsfjorden, which melts rapidly and is connected to the North-East Greenland Ice Stream (NEGIS).

Although it may be biting cold over the water, heat from the Earth's interior is transported to the bottom water of Young Sound, North-East Greenland. Credit: Wieter Boone

By focusing on an isolated basin in the fjord with a depth range between 200 and 340 m, the researchers have measured how the deep water is heated over a ten-year period. Based on the extensive data, researchers have estimated that the loss of heat from the Earth's interior to the fjord is about 100 MW m-2. This corresponds to a 2 megawatt wind turbine sending electricity to a large heater at the bottom of the fjord all year round.

Heat from the Earth's interior—an important influence

It is not easy to measure the geothermal heat flux—heat emanating from the Earth's interior—below a glacier, but within the area there are several large glaciers connected directly to the ice sheet. If the Earth releases heat to a fjord, heat also seeps up to the bottom part of the glaciers. This means that the glaciers melt from below and thus slide more easily over the terrain on which they sit when moving to the sea.

"It is a combination of higher temperatures in the air and the sea, precipitation from above, local dynamics of the ice sheet and heat loss from the Earth's interior that determines the mass loss from the Greenland ice sheet," explains Soren Rysgaard.

Sampling in Young Sound in spring where the sea ice still lies as a solid lid on the fjord. Credit: Søren Rysgaard

"There is no doubt that the heat from the Earth's interior affects the movement of the ice, and we expect that a similar heat seepage takes place below a major part of the ice cap in the north-eastern corner of Greenland," says Soren Rysgaard.

The researchers expect that the new discoveries will improve the models of ice dynamics, allowing better predictions of the stability of the Greenland , its melting and the resulting global water rise.

Explore further: Machine learning predicts new details of geothermal heat flux beneath the Greenland Ice Sheet

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16 comments

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Benni
1 / 5 (8) Jan 22, 2018
What a shame, Greenland's #1 tourist attraction is melting away leaving the land to it's original state of becoming green once again.

We await with baited breathe for the return of marauding Viking longboats & their earth-turning hand plows to once again start planting wheat & destroying the once pristine glacial environment.
barakn
5 / 5 (12) Jan 22, 2018
No physical evidence for wheat growing there at all. Zip, zilch, nada. The evidence for barley consists of a few scorched grains in a single layer at the bottom of one trash heap. "The find also substantiates a well-known text from about 1250, 'King's mirror (Konungs skuggsjá)', which mentions in passing that the Vikings attempted to grow grain on Greenland. It is the only report about cultivating barley that we have from that time and says: "As to whether any sort of grain can grow there, my belief is that the country draws but little profit from that source. And yet there are men among those who are counted the wealthiest and most prominent who have tried to sow grain as an experiment; but the great majority in that country do not know what bread is, having never seen it."" https://ancientfo...eenland/
Curly4
1.9 / 5 (7) Jan 22, 2018
So if this water is being warmed by heat from within the earth just what can humans do about that warming if any thing? If humans cannot do any thing about that warming is it caused by humans? And if this warming is a product of non human activity is there global warming that is caused by humans or is that also a natural event?
gkam
3.7 / 5 (3) Jan 22, 2018
Curly4, go here:
https://www.ipcc....ort/ar5/

Just read the Summary.
ColoradoBob
not rated yet Jan 22, 2018
What a shame, Greenland's #1 tourist attraction is melting away leaving the land to it's original state of becoming green once again.

We await with baited breathe for the return of marauding Viking longboats & their earth-turning hand plows to once again start planting wheat & destroying the once pristine glacial environment.

ColoradoBob
5 / 5 (6) Jan 22, 2018
What a shame, Greenland's #1 tourist attraction is melting away leaving the land to it's original state of becoming green once again.

We await with baited breathe for the return of marauding Viking longboats & their earth-turning hand plows to once again start planting wheat & destroying the once pristine glacial environment.


Your understanding of Greenland , and Vikings needs work. As barakn has pointed out so well below.
To his comments I would add that most Viking settlements were the work of the world's first real estate developers. They were trying to get people to move to their new settlements. In this case, a place called "Iceland" . So like all developers ever since, your new name for your new subdivision has to have a cherry name.
Greenland !!

ColoradoBob
5 / 5 (3) Jan 22, 2018
So if this water is being warmed by heat from within the earth just what can humans do about that warming if any thing? If humans cannot do any thing about that warming is it caused by humans? And if this warming is a product of non human activity is there global warming that is caused by humans or is that also a natural event?

It's not an either or proposition. That is , "black ice causes wrecks, therefore all wrecks are caused by black ice." More like a stack of pancakes.

And the greatest melting is in the Southwest not where this study was done.
RealityCheck
2.3 / 5 (3) Jan 22, 2018
Hi Benni, I hope you and yours are well; and ready to be more objective, better informed, re Global Climate Change factors/consequences.

Briefly: I remind of some things you may have missed/forgotten; which I long pointed out specifically re Greenland's (& Britain's) 'climatic peculiarity'...I trust this will avoid you ever again 'trying on' this 'old gag' here...
What a shame, Greenland's #1 tourist attraction is melting away leaving the land to it's original state of becoming green once again.

We await with baited breathe for the return of marauding Viking longboats & their earth-turning hand plows to once again start planting wheat & destroying the once pristine glacial environment.
Please realize:

- Warm Current patterns keep England much warmer/tolerable than would otherwise be given its latitude location WITHIN the Arctic Circle;

- Similar for Greenland coasts; and

- Increased heat in climate dynamics draws more extreme/devastating 'Arctic blasts'.

Ok? :)
Uncle Ira
5 / 5 (8) Jan 22, 2018
@ Really-Skippy. How you are Cher? I am fine and dandy, thanks for asking.

- Warm Current patterns keep England much warmer/tolerable than would otherwise be given its latitude location WITHIN the Arctic Circle;


Psst, Skippy, England is not WITHIN the Arctic Circle. Other than that you might have a pretty good theory going.
jonesdave
5 / 5 (7) Jan 22, 2018
Warm Current patterns keep England much warmer/tolerable than would otherwise be given its latitude location WITHIN the Arctic Circle;


Err, nope. Just checked my location, and I'm ~50 N. Admittedly, Scotland is further north, but nowhere near 66.5 N!

Geordie13
5 / 5 (5) Jan 22, 2018
I presume the heat loss should be in milli-watt /sq m- mW m-2 not MW m-2.
TechnoCreed
5 / 5 (1) Jan 22, 2018
I presume the heat loss should be in milli-watt /sq m- mW m-2 not MW m-2.

Indeed https://upload.wi...flow.jpg
Whydening Gyre
5 / 5 (3) Jan 22, 2018
@ Really-Skippy. How you are Cher? I am fine and dandy, thanks for asking.

- Warm Current patterns keep England much warmer/tolerable than would otherwise be given its latitude location WITHIN the Arctic Circle;


Psst, Skippy, England is not WITHIN the Arctic Circle. Other than that you might have a pretty good theory going.

Was gonna answer that one, but I just knew you were waiting in the grass, ready to pounce...:-)
Bongstar420
not rated yet Jan 23, 2018
Derp..

Also, it shouldn't be called "heat loss" because at no point should anyone expect for the molten core to not cool over time. Its not that the term is inaccurate, because the core is indeed losing heat, but that it creates this "frame" of thinking. Finally, we know that there is a lot of volcanic activity in the region, so it should go without saying and this is confirming assumptions rather than some revelation.

In other words, there literal volcanoes under the ice!
RealityCheck
1 / 5 (2) Jan 23, 2018
@Uncle Ira, @jonesdave and Benni.

@Ira and @dave. Sorry for the tardy reply, and thanks for your (much appreciated) correction re Britain's latitude. The only excuse I can offer is my haste (busy of late and wanted to log out quick) in composing and editing my rushed post, and incorrectly placing Britain within arctic circle as such. I should have said "VERY NEAR TO the same latitude as SIBERIA"; instead of "within arctic circle". Thanks again for picking that up, guys. :)

@Benni. I trust you got the point anyway despite my earlier misspeak now corrected, mate? Good luck. :)
leetennant
5 / 5 (3) Jan 23, 2018
What a shame, Greenland's #1 tourist attraction is melting away leaving the land to it's original state of becoming green once again.

We await with baited breathe for the return of marauding Viking longboats & their earth-turning hand plows to once again start planting wheat & destroying the once pristine glacial environment.


One wonders how long Benni thinks it takes for a glacier to form. That alone proves his point fallacious.

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